A story on Minnesota’s Top 50 largest employers in this week’s Business Journal dives into some reasons why — M&A activity chief among them — but there wasn’t room for all the details in the story. Here’s some of the more interesting things that were left out:

HeatlhPartners — which ranked No. 1 in employee growth — is running out of room at several of its locations, notably specialty-care facilities in St. Paul (near Regions Hospital) and Park Nicollet’s offices in St. Louis Park, CEO Mary Brainerd told me. The Bloomington-based health provider and insurer is weighing a variety of commercial real estate options, she said. HealthPartners’ Minnesota employee count was up by 77 percent since our last list ran in 2011, largely due to its acquisition of Park Nicollet Health Services. Growth beyond employees inherited through acquisition was roughly split between the organization’s insurance and care-provider arms, she said.

Like many health care providers, Children’s Hospitals and Clinics is busy expanding its network of clinics to prepare for health reform. But the Minneapolis-based health care provider also is bullish on what Chief Operating Officer Dave Overman calls its “hospital-in-a-hospital” strategy. The idea is to provide pediatric services inside adult hospitals. One example is Children’s’ partnership with Ridgeview to offer pediatric care within the freestanding emergency room at the Two Twelve Medical Center in Chaska. Children’s aims to expand that part of its business going forward, Overman said.

How much does UnitedHealth Group spend on Minnesota contractors? About $130 million in 2012, according to stats the insurer sent over regarding its operations in the state. The Minnetonka-based company also spent more than $100 million on property in the state and paid more than $30 million in sales and use taxes.